Washing or cleaning agents, or cosmetic agents, usually contain scents that impart a pleasant odor to the agents. The scents also mask any odor of the other ingredients, so that the consumer receives a pleasant olfactory impression.
In the washing-agent sector in particular, scents are important constituents of the composition, since the laundry is intended to have a pleasant and, if possible, also fresh scent in both the wet and the dry state. A fundamental problem encountered when using scents is that they are more or less volatile compounds, but that a long-lasting scent effect is nevertheless desirable. The desired longevity of the scent impression is very difficult to achieve in particular with those fragrances which represent the fresh and light notes of the perfume and volatilize particularly quickly because of their high vapor pressure.
Delayed scent release can occur, for example, thanks to the carrier-bound use of scents. A carrier-bound precursor form of a scent is also referred to as a “pro-fragrance.” In this connection, international patent application WO 2007/087977 discloses the use of 1-aza-3,7-dioxabicyclo[3.3.0]octane compounds as pro-fragrances for delayed release of scent aldehydes and scent ketones by hydrolysis. An alternative possibility for delayed release of scents is represented by the use of so-called photoactivatable substances as pro-fragrances. Breakage of a covalent bond in the pro-fragrance molecule is induced by the action of sunlight or another electromagnetic radiation source of a specific wavelength, with the result that a scent is released.
WO 2011/101180 discloses the use of specific ketones as photoactivatable substances which, in the presence of light, release an active agent in a photochemical fragmentation. The aforesaid active agent possesses, for example a scenting activity that is released only in delayed fashion, and over a long time period, on a specific surface as a result of the photochemically induced breakdown. Hitherto, however, only the release of scent ketones is known. The delayed release of scents other than ketones is important, however, so that as broad a spectrum as possible of long-lasting scent impressions can be furnished to the consumer.
The object of the present invention is to furnish photoactivatable substances, constituting pro-fragrances, that permit delayed release of scent esters, in particular of cinnamic acid esters and derivatives of cinnamic acid esters.
Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description of the invention and the appended claims, taken in conjunction with the accompanying drawings and this background of the invention.